A variety of commercial processes rely on the use of fluid separation techniques to separate one or more desirable fluid components from a mixture. In particular, various such processes may involve the separation of liquid mixtures, the separation of vapors or gases from liquids, or the separation of intermingled gases.
The use of membranes for fluid separations has achieved increased popularity over other known separation techniques. Membranes, once produced into elements, are typically formed into modules or cartridges, e.g., a tube containing a plurality of membrane separation elements. Modules can be used singly or, more commonly, interconnected in series or parallel arrangements or arrays in the form of membrane skids.
One of the difficulties in building membrane skids is the need to ensure that the permeate header lines up with the flange connections at the end of the membrane pressure tube. Increasing the number of modules in an installation increases the number of flange connections that must properly aligned with a permeate header thereby increasing the difficulty of interconnecting individual modules.
In addition, a common problem associated with the use of spiral wound membranes is that each module containing the membranes is typically required to be machined to a close tolerance to assure good pressure seals. As a result, the cost for each module can be significantly increased.
Further, each of the membrane modules loaded on an individual skid requires some physical separation to accommodate installation of the individual membrane modules. Typically, membrane separation installations are constructed using a number of membrane separation modules which are stacked vertically to form a skid and create the required membrane area to process a fluid. This design requires a multitude of external connections to feed each individual membrane module and remove the processed fluid. As a result, packing of such large systems may present a problem because of the need to accommodate the input, output and permeate ports of each module.
Such individual skids are constructed using structural steel to support each set of membrane modules. Such structural steel supports, however, add weight to the overall membrane system and increase the area required to install each individual skid. Consequently, such larger systems are heavier and more expensive to manufacture due to the quantity of materials needed to produce the structural steel supports, as well as, individual tubes for each module. Such larger systems are also more complex due to the increased number of connections between the membrane modules and common headers used to deliver and remove fluids from the skid.
Thus, there is a need and a demand for separation systems which incorporate an increased number of membrane cartridges or modules in a given area. In particular, there is a need and a demand for separation systems which incorporate multiple membrane cartridges into a single pressure vessel.
There is also a need and a demand for separation systems having simplified process fluid stream connections. Further, for example, there is a need and a demand for separation systems that permit feed stream delivery to, residual stream removal from, and permeate stream removal from a multitude of membrane cartridges at a reduced number of locations.
There is a further need and a demand for separation systems that are less expensive to produce.